Application Preferences

[Barry Scott]

> On 19 Aug 2019, at 13:43, Dave via Python-list <python-list at python.org> wrote:
> 
> The plan for an app that I'm doing was to use SQLite for data and to hold the preference settings as some apps do.  The plan was changed last week to allow the user to select the location of the data files (SQLite) rather than putting it where the OS would dictate.  Ok with that, but it brings up some questions.  First, I will need to have a file that points to the location of the data file  since that can't be hard coded. Second, if I have to have a file that is likely part of the application group of files, would it make more sense to use a more traditional preferences file?  How have other Python app developers done in this case?

There are expected locations for config files and data files on each OS.

On macOS you would use ~/Library/Preferences/ and put a file or a folder of files in there.
The convention is use your website name as the base name of the  file or folder.
For example for scm-workbench I use: org.barrys-emacs.scm-workbench as the folder name for
all the scm-workbench files.

On Windows you can use a file or folder in %APPDATA% that is named after your app. You should
find the folder by doing a win32 API call to get the value. See getPreferencesDir()  in
https://github.com/barry-scott/scm-workbench/blob/master/Source/Common/wb_platform_win32_specific.py <https://github.com/barry-scott/scm-workbench/blob/master/Source/Common/wb_platform_win32_specific.py>
for how to get the value.

On Linux the XDG spec says that you should put config files in ~/.config/<app-name> and data files
in  ~/.local/share/<app-name>. Doing XDG to the spec is a little involved. I have some experimental
code that implements the logic for config the XdgConfigPath class in:
https://github.com/barry-scott/CLI-tools/blob/master/Source/smart_find/__init__.py <https://github.com/barry-scott/CLI-tools/blob/master/Source/smart_find/__init__.py>

Putting a file directly in the $HOME folder is no longer recommended.

The format of the config data you are free to choose.
I have been using JSON files recently as it allow for structured data.


Barry